{"problem":{"name":"Make it Zigzag","description":{"content":"You are given a permutation $P=(P_1,P_2,\\cdots,P_{2N})$ of $(1,2,\\cdots,2N)$. The following operation may be performed between $0$ and $N$ times (inclusive). *   Choose an integer $x$ ($1 \\leq x \\leq","description_type":"Markdown"},"platform":"AtCoder","limit":{"time_limit":2000,"memory_limit":262144},"difficulty":"None","is_remote":true,"is_sync":true,"sync_url":null,"sign":"agc058_a"},"statements":[{"statement_type":"Markdown","content":"You are given a permutation $P=(P_1,P_2,\\cdots,P_{2N})$ of $(1,2,\\cdots,2N)$.\nThe following operation may be performed between $0$ and $N$ times (inclusive).\n\n*   Choose an integer $x$ ($1 \\leq x \\leq 2N-1$). Swap the values of $P_x$ and $P_{x+1}$.\n\nPresent a sequence of operations that make $P$ satisfy the following conditions.\n\n*   $P_i<P_{i+1}$ for each $i=1,3,5,\\cdots,2N-1$;\n*   $P_i>P_{i+1}$ for each $i=2,4,6,\\cdots,2N-2$.\n\nIt can be proved that such a sequence of operations always exists.\n\n## Constraints\n\n*   $1 \\leq N \\leq 10^5$\n*   $(P_1,P_2,\\cdots,P_{2N})$ is a permutation of $(1,2,\\cdots,{2N})$.\n*   All values in input are integers.\n\n## Input\n\nInput is given from Standard Input in the following format:\n\n$N$\n$P_1$ $P_2$ $\\cdots$ $P_{2N}$\n\n[samples]","is_translate":false,"language":"English"}],"meta":{"iden":"agc058_a","tags":[],"sample_group":[["2\n4 3 2 1","2\n1 3\n\nThese operations make $P=(3,4,1,2)$, which satisfies the conditions."],["1\n1 2","0"]],"created_at":"2026-03-03 11:01:14"}}